Defensive publication



T DEFENSIVE PUBLICATION UNITED STATES PATENT OFFICE Published at the request of the applicant or owner in accordance with the Notice of Apr. 11, 1968, 849 0.G. 1221. Identiflcatlon is by serial number of the application and the heading indicates the number of pages of specification, including claims, and of sheets of drawing contained in the application as originally filed. The file of this application is available to the public for inspection; reproduction may be purchased for 30 cents per sheet.

Applications published under the Defensive Publication Program have not been examined as to the merits of alleged invention. The Patent Oflice makes no assertion as to the novelty of. the disclosed subject matter.

PUBLISHED SEPTEMBER 16, 1969 825 420 SILVER HALIDE EMU LSIONS CONTAINING METAL CHELATE FOG INHIBITORS Dorothy J. Beavers, Kodak Park Division, Rochester, N.Y. 14650 Filed May 16, 1969. Published Sept. 16, 1969 Int. Cl. G03c 1/34 U.S. Cl. 96110 No Drawing. 13 Pages Specification Photographic silver halide emulsions and photographic elements comprising said emulsions are improved against the detrimental effects of chemical and environmental fog by incorporating in said emulsions known metal chelates in effective concentrations. Said chelating metals include transition metals, actinides, lanthanides, beryllium, magnesium and the like. Enols of dehydroacetic acid, pyrithione and 1,3 diketone are preferred. Said chelated metals prepared by reacting a suitable salt of said metals with the desired chelating agents.

Silver halide emulsions and elements described can be chemically sensitized, e.g., with noble metal sensitizers alone or in combination with sulfur or selenium sensitizers. They can contain spectral sensitizers, incorporated color-forming couplers, incorporated developing agents, other antifoggants, hardeners, plasticizers, coating aids, vinyl polymers, and other suitable photographic addenda such as described in U.S. Patent 3,297,446 of Dunn issued Jan. 10, 1967 (columns 4-9). 

